"On TV debates, I'm in favour of them, I think they are good and I think we should go on having them, and I will play my part in trying to make that happen," he said.

In December the prime minister told journalists he thought the debates had taken “all the life” out of the election campaign and said he had not made up his mind about whether to take part in future clashes.

His comments led Labour to accuse him of “running scared” of Ed Miliband, suggesting he did not want to defend his record in No.10.

Cameron also told the press conference that he felt the 2010 TV debates, which gave Nick Clegg a huge, if fleeting, surge in the polls, did not change the outcome of the election.

"I think actually from memory the polls going into the start of the last election were pretty similar to the polls coming out of the last election, so I suspect the result would have been pretty much the same anyway," he said.